The explosion killed three and injured five others according to a statement issued by the movement's Gaza City office.

Egypt's continuing operations against Hamas tunneling and Hamas's condemnation of the Egyptian military both demonstrate that talks held last month between Cairo security figures and Hamas's leadership failed to resolve their disagreements.

Sinwar (Photo: AP, EPA)

The statement comes just weeks after the election of Yahya Sinwar,
considered to be on the militant end of the spectrum, as Hamas's leader in the Gaza Strip.

"This is the first time a military man is taking over the political bureau of Hamas since the organization was founded a quarter of a century ago," Mukhaimer Abusada, a political scientist at Al-Azhar University-Gaza told The Media Line. "Sinwar's election means that the military wing—the Izz ad-Din al-Qassam brigades—is taking over the movement."

Since his release from an Israeli prison in the 2011, Sinwar, 54, has organized the digging of smuggling tunnels under the Egyptian border and has been involved in re-arming the organization.

Before Sinwar's election, ordinary Gazans were hopeful about the economic benefits of a possible rapprochement between Hamas and Egypt.

Cairo was looking to Hamas for help in dealing with the Islamist terror groups in the Sinai Peninsula and Hamas leaders—including Gaza-based leader Ismail Haniyyeh—had successfully lobbied the Egyptians for more regular openings of the land border crossing at Rafah.

Just two weeks ago, Egypt's Intelligence Chief Khaled Fawzy hosted Hamas leaders Haniyyeh, Rawhi Mushtaha, and Moussa Abu Marzouk for several days of consultations aimed at burying the hatchet.

But in its condemnation of Saturday's anti-tunneling operation, Hamas renewed its call to permanently open the Rafah crossing between Gaza and Egypt, portraying Cairo as complicit with "Israel's unfair siege on Gaza Strip."

Internal politics drives the deterioration in Egypt ties, and likelihood of war with Israel.

In addition to the day-to-day administration of the Gaza Strip, the Hamas political bureau decides policy and allocates funds raised by the group from Palestinian and foreign donors—chief among them Qatar and Turkey, who identify with its ideological and historical roots in Egypt's now outlawed Muslim Brotherhood.

Sinwar replaces outgoing leader Ismail Haniyyeh who has worked in recent years to boost Qatari financial support and regain Saudi and Egyptian trust.

The Saudis and Qataris—staunch Sunni Muslims—have expressed concerns with the group's ties to the Iranian military and to Hezbollah who are effectively governed by Shi'a clerics.

Haniyyeh has visited both Iran and Saudi Arabia over the course of the past year and his talks with princes in Riyadh were instrumental in getting Egypt to open the dialogue with Hamas.

But Haniyyeh, now running to succeed to Hamas's top leader Khaled Meshaal—who lives in a self-determined exile in the Gulf—dismissed the distinction between the group's military and political activities at the Friday mosque dedication ceremony in Gaza City.

"The Zionist media are trying to distinguish between the military and political figures (in Hamas), but we tell them we are all fighters and that in the face of the occupation we are all military," Haniyyeh said.

With Hamas leaders ramping up the militant rhetoric in advance of the Palestinian local elections –now scheduled for May—and with factions competing to prove their commitment to anti-Israel "resistance"–political scientist Abu Sada says a renewed conflict with Israel seems more likely than ever.

"I hate to say it, but it seems to me that we need to start counting down the days to the next war," said Abusada.